| (19) |
 |
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(11) |
EP 0 235 986 B2 |
| (12) |
NEW EUROPEAN PATENT SPECIFICATION |
| (45) |
Date of publication and mentionof the opposition decision: |
|
21.04.1999 Bulletin 1999/16 |
| (45) |
Mention of the grant of the patent: |
|
03.07.1991 Bulletin 1991/27 |
| (22) |
Date of filing: 12.02.1987 |
|
|
| (54) |
Slow release formulation
Formulierung mit langsamer Freisetzung
Formulation à libération lente
|
| (84) |
Designated Contracting States: |
|
AT BE CH DE ES FR GB GR IT LI LU NL SE |
| (30) |
Priority: |
13.02.1986 GB 8603523
|
| (43) |
Date of publication of application: |
|
09.09.1987 Bulletin 1987/37 |
| (73) |
Proprietor: ETHICAL PHARMACEUTICALS LIMITED |
|
Cambridgeshire CB7 4EE (GB) |
|
| (72) |
Inventor: |
|
- Rhodes, Alan
Ely
Cambridgeshire (GB)
|
| (74) |
Representative: Allard, Susan Joyce et al |
|
BOULT WADE TENNANT,
27 Furnival Street London EC4A 1PQ London EC4A 1PQ (GB) |
| (56) |
References cited: :
EP-A- 0 014 514 GB-A- 1 033 484 GB-A- 1 137 379 US-A- 2 809 916 US-A- 3 065 143
|
EP-A- 0 097 523 GB-A- 1 137 379 JP-A- 4 320 006 US-A- 2 809 916 US-A- 3 946 110
|
|
| |
|
|
- Remington's pharmaceutical Science, 17th ed. (1985) 1065-6
- Int. J. Pharm. Techn. & Prod. Mfr., 5 (3) 1-9, 1984
|
|
| |
|
|
|
Remarks: |
|
The file contains technical information submitted after the application was filed
and not included in this specification |
|
[0001] The present invention relates to a slow release formulation for pharmaceutical or
veterinary use.
[0002] The use of slow release formulations (also known as controlled release or sustained
release formulations) is well established in medicine and the value of slow release
formulations is widely appreciated. Slow release formulations have the advantage that
the active compound is released over a relatively long period so that the active compound
is maintained in the blood stream for a longer time and at a more uniform concentration
than would otherwise be the case. It is also known to formulate slow release preparations
to release the active compound only when the preparation has reached a certain part
of the digestive system.
[0003] Many different proposals have been put forward for slow release formulations. One
proposal for a slow release formulation is put forward in British Patent No 1021924
: in the process of this patent the medicament is admixed with a comminuted sustained
release material to obtain a dry mixture which is subsequently pressed into tablets.
The sustained release material is said to be advantageously used in amounts of as
much as 95%, a very high proportion indeed.
[0004] It is also known to prepare slow release formulations by incorporating active ingredient
in a water insoluble binder which will disperse only very slowly in the alimentary
system. For example, British Patent No 1137379 discloses a multi-stage formulation
process in which ethylcellulose (which is water insoluble) is used as binder in the
initial step. It would appear that in GB 1137379 insufficient alcohol is used in the
initial processing to dissolve the ethylcellulose and thus a matrix (i.e. a uniform,
continuous phase) is not formed. The process disclosed is very complex and would not
be economical.
[0005] Another controlled release formulation which utilizes a water insoluble polymer is
US Patent No 3962414. The polymer of US 3962414 is initially water soluble but is
cross-linked with polyvalent metal cations in the final formulations, and the patent
discloses three different structures which use the cross-linked polymer to release
drugs to the eye.
[0006] British Patent No 1486288 describes a water insoluble matrix which holds an active
substance (e.g. a drug). EP 0094513 covers a device having not a water soluble matrix
but a biodegradable one. The device is suitable for use as an implant, because the
release of active material has a duration of several months or more and is achieved
by biodegradation of the polymers comprising the system.
[0007] US Patent No 2809916 discloses a formulation process using repeated steps (processes
using 9 to 15 steps are exemplified) of mixing a drug with water insoluble excipient,
drying and granulating. At each granulation step the mix is granulated to the same
size and the result of such a process is a uniform and intimate mixture of excipient
and active ingredient. The reason for carrying out the multistage process is apparently
that sufficient excipient could not be combined with the active ingredient in one
step - if all the excipient were added in one step the result would be an unworkable
slurry. The US patent states that by increasing the number of mixing-drying steps
the rate of release of the drug is slowed but it is to be expected that when the amount
of insoluble binder is increased in this way the rate of release will be slowed.
[0008] A two stage formulation process is also disclosed in Example 8 of US Patent No 3946110,
in which aspirin powder is first mixed with pectin, then granulated and mixed with
potato starch and silica. The potato starch, however, acts not as a slow release binder
but as a disintegrator to accelerate release of aspirin. The inclusion of silica is
for absorption of atmospheric moisture before this has a chance to react with the
aspirin to form acetic and salicylic acids.
[0009] We have now appreciated that there remains a need for an economical slow release
formulation. In particular, it would be desirable to provide slow release formulations
which need only include cheap and readily available excipients and which can be made
using existing machinery.
[0010] According to the present invention there is provided a slow release formulation to
be administered to humans or animals, comprising (a) primary granules which comprise
particles comprising an active ingredient and a primary matrix of water soluble slow
release material in which are dispersed the particles comprising the active ingredient,
and (b) a secondary matrix of a water soluble slow release material in which the granules
are dispersed, the secondary matrix and the primary granules forming secondary granules,
wherein a polysaccharide material or alginate forms the slow release material of one
or both matrixes
[0011] The formulation comprises secondary granules which comprise primary granules within
a secondary matrix of a water soluble slow release material, the primary granules
themselves comprising particles comprising an active ingredient within a primary matrix
of a water soluble slow release material.
[0012] Also included in the invention is a method of making slow release formulations. In
the method, particles comprising an active ingredient are mixed together with a solution
or dispersion of a water soluble slow release material, to form an agglomerate which
is granulated. The resultant primary granules, after drying, are mixed together with
a solution or dispersion of a water soluble slow release material to form an agglomerate.
The agglomerate is then granulated to form secondary granules of a larger size than
the primary granules and dried. The second granulation step is necessary to obtain
a suitable dosage form for administration. The secondary granules as such could be
used as the dosage form and could be administered by, for example sprinkling on food.
More usually, however, the second granulation step is necessary for further processing
to form tablets or capsules for oral adminsitration. Although oral dosage forms are
preferred, it is envisaged that the secondary granules could be incorporated in suppositories
or implants.
[0013] The slow release formulations of the invention may be called "multi-matrix formulations",
since they comprise at least a primary matrix of slow release material binding the
particles containing the active ingredient to form primary granules and a secondary
matrix of slow release material which binds the primary granules together. Surprisingly,
we have found that a multi-matrix formulation releases the active ingredient over
a substantially longer period than a single matrix formulation containing the same
proportions of active ingredient and slow release material.
[0014] The slow release formulations of the invention may alternatively be defined as comprising
particles which comprise an active ingredient and are arranged as clusters of relatively
densely packed particles dispersed in water soluble matrix material. The matrix material
at the clusters (i.e. the primary matrix) may be the same as or different to the matrix
material between the clusters (i.e. the secondary matrix).
[0015] The method of the invention is a "building up" process in which, because the second
granulating step produces larger granules than the first step, there is built up the
non-uniform or discontinuous multi-matrix structure. This method should be distinguished
from the homogenising multi-stage granulation process of US Patent No 2809916 in which
each granulation is to the same size and there is no building up and a uniform structure
is achieved which is continuous in the sense that there are no sharp changes in the
pattern of medicament dispersion.
[0016] The invention is not restricted as to the active ingredient and any one or more active
ingredients may in principle be used. For example, the formulations may contain aminophylline,
theophylline or another bronchodilator, for the treatment of asthma or bronchitis.
Alternatively, the active ingredient may, for example, be a tranquiliser, e.g. hydroxyzine,
chlordiazepoxide or chlorpromazine hydrochloride. Other possible active ingredients
are analgesics (e.g. morphine), antibiotics or antihypertensives (e.g. propranalol).
[0017] The same or different slow release materials may be used in the different matrixes.
The water soluble material of the matrixes is a polysaccharide or alginate which can
be used as a pharmaceutical, or appropriately, veterinary binder and which is slowly
soluble in water e.g. a cellulose derivative, especially methylcellulose, or other
polysaccharide. Another preferred water soluble binder is acacia (gum arabic), optionally
in admixture with another binder, such as tragacanth, agar, sterculia or starch, for
example. When in admixture, the acacia generally forms substantially 50 wt% or more
of the mixture. Some or all of the acacia may be replaced with apricot gum.
[0018] The matrixes consist of water soluble materials which can thus be applied in an aqueous
medium. In the case of active ingredients which might be adversely affected by water
(e.g. would be susceptible to hydrolysis) it may be preferable to use a pharmaceutically
acceptable organic solvent or dispersant, for example a lower alkanol, especially
methanol, ethanol or isopropanol, or a haloalkane, especially chloroform or methylene
chloride. Suitable mixtures may also be used, e.g. aqueous ethanol or methanol.
[0019] Matrix material is used in the process in solution or dispersion to ensure thorough
mixing with the admixed material and the formation of a homogenous matrix structure.
[0020] The secondary granules may be bound in a binder phase of a water insoluble slow release
material. If a water insoluble slow release material is used to bind granulated double
matrix composition, a lipid material as described in British Patent No 1021924 may
be chosen to form the binder phase. We have found hydrogenated castor oil to be satisfactory
but any other lipid material referred to in GB 1021924 may be used, for example. As
examples there may be mentioned mineral, vegetable or animal waxes, a C
24-C
62 ester of a C
12-C
31 fatty acid and C
12-C
31 fatty alcohol, a C
10-C
22 fatty acid, a C
10-C
22 fatty alcohol or a mono-, di- or triglycerol ester of a C
10-C
22 fatty acid. Especially preferred are hydrogenated castor oil, glyceryl mono- or distearate,
12-hydroxystearyl alcohol and micro-crystalline wax.
[0021] In addition to the active ingredient and the slow release materials, the formulations
of the invention may include other components in any portion of the formulation, for
example fillers (e.g. lactose, bentonite, calcium phosphate, glycine, calcium carbonate,
kaolin, sucrose), lubricants (e.g. boric acid, cacao oil, paraffin, polyethylene glycol,
talc, stearates, stearic acid), preservatives (e.g. methyl or ethyl p-hydroxybenzoate),
absorption proroters (e.g. glycerin mono- or di-medium sized alkanoates), antioxidants,
flavourings, edible colouring agents and stabilizing agents.
[0022] The formulations of the invention may be formulated into forms for oral administration
(tablets or capsules) and may be for either medical or veterinary use. In the preparation
of tablets or capsules, the secondary granules may be dispersed in a water insoluble
binder phase as described above prior to being formed into tablets or capsules. If
desired, the tablets or capsules may be enteric, film or sugar coated. Instead of
being formulated into oral dosage form, it would be feasible to process the formulations
of the invention into suppositories or implants, in which case the secondary granules
would generally be embedded in a water insoluble binder phase.
[0023] The proportions of the different ingredients are not critical but the sustained release
material of the matrixes generally amounts to 1 to 50% by weight of the total solids
of the matrix material and the particles containing the active ingredient. Preferably,
the amount of the sustained release material of the matrixes is of from 1.5 to 15%
by weight of the total solids of the matrix material and the particles containing
the active ingredient. The particular amount of sustained release material chosen
will vary from application to application and can be determined by the skilled person
for each case.
[0024] The active ingredient or ingredients plus any diluents generally form from 50 to
99%, more usually from 85 to 98.5% by weight of the total solids of the matrixes and
the particles containing the active ingredients.
[0025] If the formulations include a binder phase, this may constitute from 1 to 50% by
weight of the total solids of the formulation, for example, although in some instances
higher quantities might be desirable. Preferably, the binder phase amounts to 5 to
25% by weight of the total solids.
[0026] Other minor ingredients generally amount to a few percent of the total solids of
the formulations, e.g. from 0.5 to 5% by weight.
[0027] The invention is further described by way of example only with reference to the accompanying
drawings, in which :
Figure 1 is a flow chart illustrating a method of preparation of the formulations
of the invention ;
Figure 2 is a schematic illustration of a formulation prepared by the method illustrated
in Figure 1 ;
Figure 3 is a graph comparing the dissolution of a formulation of the invention with
a single matrix formulation prepared with the same ingredients in the same proportions
;
Figure 4 is a graph of mean plasma theophylline concentration following administration
to volunteers of a double matrix aminophylline formulation of the invention and a
comparative marketed slow release formulation manufactured in accordance with British
Patent No 1405088.
Figure 5 is a graph illustrating the influence of double matrix processing of a theophylline/methyl
cellulose formulation ; and
Figure 6 is a graph of mean plasma theophylline concentration following administration
to volunteers of a theophylline formulation of the invention and a comparative marketed
slow release formulation.
[0028] Turning to Figure 1, in a preferred method of the invention, a powder of the active
ingredient is blended, for example in a conventional mixer, with an aqueous solution
or dispersion of a water soluble sustained release binder to form an agglomerate.
The solution or dispersion is desirably relatively concentrated, for example a solution
of 1 part by weight of acacia in 1 to 2 parts, preferably 1.25 to 1.8 parts, by weight
of purified water. The use of a concentrated solution makes handling and drying of
the resultant mixture relatively easy.
[0029] The wet mixture is then dried, for example on a fluid bed drier. A temperature of
35°C to 60°C is suitable for the drying. After being dried, the mixture is passed
through a dry granulator of relatively fine mesh aperture (e.g. 600 to 250 micrometre
mesh aperture, preferably 500 to 355 micrometre) and, if necessary, may be further
dried.
[0030] The single matrix granules now obtained are then subjected to the same procedure
again. They are mixed with binder solution (often but not necessarily the same solution
as used in the first stage), dried and granulated (generally to 2 mm to 1 mm mesh
aperture).
[0031] Step 5 of Figure 1 is optional and thus the secondary granules may now be directly
compressed into tablets or encapsulated or they may be dry blended with a water insoluble
binder (e.g. hydrogenated castor oil) and compressed in a tablet press. The tablets
may subsequently be coated, e.g. with an enteric coating. It will be seen that the
whole process may be carried out using conventional apparatus. Of course, the secondary
granules may be processed into a dosage form other than tablets or capsules.
[0032] Figure 2 is a schematic cross-section through a portion of a tablet obtained after
step 6 of the process of Figure 1. The tablet comprises a binder phase 5 of a water
insoluble binder in which there are embedded double matrix or secondary granules 6
containing the active ingredient. The secondary granules 6 themselves comprise single
matrix or primary granules 1 in a secondary matrix 2 of sustained release binder.
In turn, the primary granules 1 comprise particles 3 containing the active ingredient
in a primary matrix 4 of sustained release binder.
[0033] If desired, the above described process may be modified by adding to the formulation
at an appropriate stage a filler or other additional component.
[0034] The above described process may be modified in a number of ways, as will be apparent
to the skilled person. For example, when using methylcellulose as one or both matrixes
it might be advantageous in steps 1 and/or 3 of Figure 1 to, firstly, dry blend high
viscosity methylcellulose and, respectively, the particles containing the active ingredient
or the single matrix granules and subsequently to mix the dry blend with a solution
of low viscosity cellulose. Alternatively, the slow release material of one or both
matrixes could initially be dry blended with the particles containing the active ingredients
or the single matrix granules and subsequently water or another liquid (e.g. ethanol)
would then be added to the dry blend and mixed therewith.
[0035] The water insoluble binder, instead of being dry blended with the double matrix granules
could be added as a melt or in an organic solvent, for example ethanol.
[0036] It is further contemplated that the process could be modified to obtain triple matrix
granules by repeating steps 3 and 4 of Figure 1 after step 4. However, in this case
in stage 2 the mixture would generally be granulated more finely then would otherwise
be the case, and the third granulation step would be to a larger granule size than
the second granulation step.
[0037] The following Examples illustrate the invention :
Example 1
[0038]
| FORMULA First Mix |
| Aminophylline |
1000g |
| Acacia |
50g |
| Purified water |
75ml |
| Second Mix |
| Acacia |
50g |
| Purified water |
75ml |
| Binder Phase |
| Cutina HR (Hydrogenated castor oil) |
200g |
Method
[0039]
1) Add the 50 g acacia dissolved in 75 ml water to the aminophylline in a mixer (Baker
Perkins) under conditions of 100 rpm main impeller. Increase the speed to 500 rpm
main/1000 rpm side and mix for 5 minutes. Scrape down and mix for 5 minutes and scrape
down again and mix for a further 5 minutes.
2) Discharge the formed granules, fluid bed dry at 40°C for 5 minutes and granulate
to 500 um mesh aperture size.
3) Granulate to 355 um mesh aperture size and fluid bed dry for 5 minutes at 40°C.
4) Place the dried granules back into the mixer and mix in the second portion of acacia
dissolved in water.
5) Granulate to 1.4 mm mesh aperture size, fluid bed dry at 40°C for 5 minutes, and
repeat this procedure twice.
6) Blend in the Cutina and compress under power in a Manesty F3 tablet press.
[0040] There were obtained 20 smooth white to light grey tablets free from pits or blemishes
with a slightly discernable matrix structure.
Dissolution in water
[0041]
Mean Amount dissolved in 1 hr = 48%
Mean Amount dissolved in 2 hr = 69%
Mean Amount dissolved in 3 hr = 85%
Mean Amount dissolved in 4 hr = 94%
Mean Amount dissolved in 5 hr = 98%
[0042] The dissolution rate obtained with tablets of the invention was compared with conventional
single matrix tablets prepared by the procedure given in the following Comparative
Example.
Comparative Example
[0043]
| FORMULA |
| Aminophylline |
100g |
| Acacia |
10g |
| Purified water |
15ml |
| Cutina HR |
20g |
Method
[0044] The acacia in water was mixed with the aminophylline using a mortar and pestle before
drying and granulating to form a 1.4 mm mesh aperture size granule. The Cutina was
then dry blended and the product compressed under power on a Manesty F3 tablet press.
Dissolution
[0045]
Mean Amount dissolved in 1 hr = 70%
Mean Amount dissolved in 2 hr = 97%
[0046] The use of a single as opposed to double matrix of acacia for the aminophylline granules
has resulted in an unexpectedly drastic increase in the rate of tablet dissolution
as best demonstrated by Figure 3, which is a graph of the dissolution rates of the
tablets obtained in Example 1 and those obtained in the Comparative Example.
In vivo study of the tablets obtained in accordance with the general method of Example
1
[0047] A study was undertaken in 4 healthy young volunteers wherein on each of 2 separate
occasions, separated by at least a seven day washout period to permit "washing out"
of aminophylline from the volunteers, each subject was administered either a 225 mg
aminophylline tablet prepared using a method like that of Example 1, or a commercially
available 225 mg slow release aminophylline tablet formulated in accordance with British
Patent No 1405088. Blood samples were obtained on administration of each test preparation
and at suitable time intervals thereafter and subsequently analysed for plasma theophylline
concentration (the active moiety of aminophylline). Figure 4 shows the mean plasma
theophylline concentration versus time profiles obtained. As can be seen the tablets
produced according to the present invention result in plasma theophylline concentrations
similar to those obtained by the marketted slow release aminophylline preparation.
Example 2
[0048]
| Formula |
Amount |
| Theophylline Monohydrate |
1100g |
| Methyl Cellulose (low viscosity) |
20g |
| Purified Water |
450ml |
| Talc |
11g |
| Mg. stearate |
11g |
[0049] Utilising the above formula batch 1 was processed according to the double matrix
procedure and batch 2 was processed by a single matrix procedure. Both batches utilised
a solution of the methyl cellulose in water and both were processed to a final granule
size of 1.4 mm prior to dry blending with the lubricants (talc and magnesium stearate)
and compression to 400 mg anhydrous theophylline tablets.
[0050] On testing for dissolution in degassed, distilled water at 37°C using the USP 'Paddle'
procedure, at 100 rpm mixing speed, the two batches gave the following results.
| |
% in solution |
| Time (hrs.) |
Batch 1 (Double Matrix) |
Batch 2 (Single Matrix) |
| 1 |
17 |
20 |
| 2 |
24 |
32 |
| 3 |
31 |
44 |
| 4 |
37 |
54 |
| 5 |
41 |
64 |
| 6 |
47 |
72 |
| 7 |
51 |
80 |
| 8 |
55 |
89 |
[0051] These results are further presented graphically in Fig. 5 where the difference in
rates of dissolution of the two preparations becomes very apparent.
[0052] Again the double matrix formulation (Batch 1) was used in a bioavailability study
(4 subjects), the results of which are shown in Fig. 6 in comparison to a single dose
of 2 × 200 mg tablets of the reference slow release theophylline preparation. As before
tablets prepared according to the present invention produced very similar results
to those obtained with the reference marketed slow release theophylline tablets.
Example 3
[0053] The use of sodium alginate as the matrix material is shown in this Example.
| Formula |
Amount |
| Theophylline Monohydrate |
550g |
| Sodium Alginate |
10g |
| 95% Ethanol |
20ml |
| Purified Water |
250ml |
| Magnesium Stearate |
5.6g |
[0054] In the above formula the ethanol is present as a dispersant for the sodium alginate
to enable thorough dissolution in the aqueous granulating medium. Batches 3 and 4
were respectively processed by the single and double matrix procedures using the above
formula. Finished tablets from the 2 batches were assessed for dissolution rate by
the USP 'Paddle' procedure ; degassed distilled water @ 37°C ; 100 rpm paddle speed
to yield the following data :
| |
% in solution |
| Time (hrs) |
Batch 3 (Single Matrix) |
Batch 4 (Double Matrix) |
| 1 |
44 |
34 |
| 2 |
76 |
61 |
| 3 |
94 |
87 |
[0055] Again the slowing of dissolution when tablets are processed by the double as opposed
to single matrix method is readily apparent.
Claims for the following Contracting State(s): BE, CH, DE, FR, GB, IT, LI, LU, NL
1. A slow release formulation to be administered to human or animals, comprising (a)
primary granules (1) which comprise particles (3) comprising an active ingredient
and a primary matrix (4) of water soluble slow release material in which are dispersed
the particles (3) comprising the active ingredient, and (b) a secondary matrix (2)
of a water soluble slow release material in which the granules (1) are dispersed,
the secondary matrix (2) and the primary granules (1) forming secondary granules (6),
wherein a polysaccharide material or alginate forms the slow release material of one
or both matrixes (2,4).
2. A slow release formulation as claimed in claim 1 wherein both matrixes (2,4) are formed
of the same slow release material.
3. A slow release formulation as claimed in claim 1 or claim 2 wherein the slow release
material is a cellulose derivative.
4. A slow release formulation as claimed in any one of the preceding claims wherein the
secondary matrix-granule composition is itself in the form of granules (6) in a binder
phase of a water insoluble slow release material, for example one or more of a mineral,
vegetable or animal wax, a C24-C62 ester of a C12-C31 fatty acid and a C12-C31 fatty alcohol, a C10-C22 fatty acid, a C10-C22 fatty alcohol, or a mono-, di- or triglyceryl ester formed from a C10-C22 fatty acid and preferably one or more of hydrogenated caster oil, glyceryl mono-
or distearate, 12-hydroxystearyl alcohol or micro-crystalline wax.
5. A method of making a slow release formulation to be administered to humans or animals,
comprising mixing particles comprising an active ingredient and a solution or dispersion
of a water soluble slow release material which is a polysaccharide or alginate to
form an agglomerate and granulating the agglomerate, drying the resultant primary
granules and mixing them with a solution or dispersion of a water soluble slow release
material which is a polysaccharide or alginate to form an agglomerate and granulating
the agglomerate to form secondary granules of a larger size than the primary granules,
and drying the secondary granules, and optionally blending the secondary granules
with a water insoluble slow release material.
6. A method as claimed in claim 5 wherein the liquid vehicle of each solution or dispersion
is water or a pharmaceutically acceptable organic liquid (preferably ethanol, methanol,
aqueous ethanol, aqueous methanol, chloroform, isopropanol or methylene chloride).
7. A method as claimed in claim 5 or claim 6, which has two granulating steps and wherein
in the first granulating step the mixture is granulated to a size of 600 micrometre
to 250 micrometre mesh aperture and in the second granulating step the mixture is
granulated to a size of 2 mm to 1 mm mesh aperture.
8. A method as claimed in any one of claims 5 to 7 wherein the particles containing active
ingredient or the primary granules or both are dry blended with a slow release material
(e.g. high viscosity methylcellulose) and subsequently admixed with a solution of
a slow release material (e.g. high viscosity methylcellulose).
9. A slow release formulation as claimed in any one of claims 1 to 4 or a method as claimed
in any one of claims 5 to 8, wherein the formulation is formulated for oral administration.
Claims for the following Contracting State(s): AT, ES, GR,
1. A method of making a slow release formulation to be administered to humans or animals,
comprising mixing particles comprising an active ingredient and a solution or dispersion
of a water soluble slow release material which is a polysaccharide or alginate to
form an agglomerate and granulating the agglomerate, drying the resultant primary
granules and then mixing them with a solution or dispersion of a water soluble slow
release material which is a polysaccharide or alginate to form an agglomerate and
granulating the agglomerate to form secondary granules of a larger size than the primary
granules, and drying the secondary granules.
2. A method as claimed in claim 1 wherein the liquid vehicle of each solution or dispersion
is water or a pharmaceutically acceptable organic liquid, preferably ethanol, methanol,
aqueous ethanol, aqueous methanol, chloroform, isopropanol or methylene chloride.
3. A method as claimed in claim 1 or claim 2, wherein the water soluble materials used
in the first and second mixing steps are the same.
4. A method as claimed in any one of the preceding claims wherein the slow release material
is a cellulose derivative.
5. A method as claimed in any one of claims 1 to 4, which has two granulating steps and
wherein in the first granulating step the mixture is granulated to a size of 600 micrometre
to 250 micrometre mesh aperture and in the second granulating step the mixture is
granulated to a size of 2 mm to 1 mm mesh aperture.
6. A method as claimed in any one claims 1 to 5, wherein the particles containing active
ingredient or the primary granules or both are dry blended with a slow release material
(e.g. high viscosity methylcellulose) and subsequently admixed with a solution/dispersion
of a slow release material (e.g. low viscosity methylcellulose).
7. A method as claimed in any one of claims 1 to 6 which further comprises blending the
secondary granules with a water insoluble slow release material.
8. A method as claimed in claim 8 wherein the water insoluble slow release material is
formed of one or more of a mineral, vegeteble or animal wax, a C24-C62 ester of a C12-C31 fatty acid and a C12-C31 fatty alcohol, a C10-C22 fatty acid, a C10-C22 fatty alcohol, or a mono-, di- or triglyceryl ester formed from a C10-C22 fatty acid, and preferably of one or more of hydrogenated caster oil, glyceryl mono-
or distearate, 12-hydroxystearyl alcohol or micro-crystalline wax.
9. A method as claimed in any one of the preceding claims, wherein the formulation is
formulated for oral administration.
Patentansprüche für folgende(n) Vertragsstaat(en): BE, CH, DE, FR, GB, IT, LI, LU,
NL
1. An Menschen oder Tiere zu verabreichende Formulierung mit langsamer Freisetzung, umfassend
(a) Primärgranulate (1), welche einen aktiven Bestandteil umfassende Teilchen(3) und
eine Primärmatrix (4) aus wasserlöslichem langsam freisetzendem Material, worin die
den wirksamen Bestandteil enthaltenden Teilchen (3) dispergiert sind, umfassen, und
(b) eine Sekundärmatrix (2) aus einem wasserlöslichen langsam freisetzenden Material,
worin die Granulate (1) dispergiert sind, wobei die Sekundärmatrix (2) und die Primärgranulate
(1) Sekundärgranulate (6) ausbilden, worin ein Polysaccharidmaterial oder ein Alginat
das langsam freisetzende Material einer oder beider Matrices (2,4) ausbildet.
2. Formulierung mit langsamer Freisetzung nach Anspruch 1, worin beide Matrices (2,4)
aus dem gleichen langsam freisetzenden Material gebildet sind.
3. Formulierung mit langsamer Freisetzung nach Anspruch 1 oder 2, worin das langsam freisetzende
Material ein Cellulosederivat ist.
4. Formulierung mit langsamer Freisetzung nach einem der vorstehenden Ansprüche, worin
die Sekundärmatrix-Granulatzusammensetzung ihrerseits in Form von Granulaten (6) in
einer Bindemittelphase aus einem wasserunlöslichen langsam freisetzenden Material
besteht, beispielsweise aus einem oder mehreren mineralischem, vegetabilem oder tierischem
Wachs, einem C24-C62-Ester einer C12-C31-Fettsäure und eines C12-C31-Fettalkohols, einer C10-C22-Fettsäure, einem C10-C22-Fettalkohol oder einem Mono-, Di- oder Triglycerylester einer C10-C22-Fettsaure und vorzugsweise aus einem oder mehreren Vertreter aus hydriertem Rizinusöl,
Glycerylmono- oder -distearat, 12-Hydroxystearylalkohol oder mikrokristallinem Wachs.
5. Verfahren zur Herstellung einer an Menschen oder Tiere zu verabreichenden Formulierung
mit langsamer Freisetzung, umfassend ein Vermischen von einen wirksamen Bestandteil
enthaltenden Teilchen und einer Lösung oder Dispersion eines wasserlöslichen langsam
freisetzenden Materials, bei dem es sich um ein Polysaccharid oder ein Alginat handelt,
zur Ausbildung eines Agglomerats und ein Granulierren des Agglomerats, ein Trocknen
der gebildeten Primärgranulate und ein Mischen dieser Granulate mit einer Lösung oder
Dispersion eines wasserlöslichen langsam freisetzenden Materials, bei dem es sich
um ein Polysaccarid oder ein Aliginat handelt, zur Ausbildung eines Agglomerats und
ein Granulieren des Agglomerats zur Ausbildung von Sekundärgranulaten mit größeren
Abmessungen als die Primärgranulate und ein Trocknen der Sekundärgranulate und gegebenenfalls
ein Vermischen der Sekundärgranulate mit einem wasserlöslichen langsam freisetzenden
Material.
6. Verfahren nach Anspruch 5, worin der flüssige Träger jeder Lösung oder Dispersion
Wasser oder eine pharmazeutisch annehmbare organische Flüssigkeit, (vorzugsweise Ethanol,
Methanol, wäßriges Ethanol, wäßriges Methanol, Chloroform, Isopropanol oder Methylenchlorid)
ist.
7. Verfahren nach Anspruch 5 oder 6, welches zwei Granulierstufen aufweist und worin
in der ersten Granulierstufe das Gemisch auf eine Größe von 600 µm bis 250 µm Maschenöffnung
granuliert wird und in der zweiten Granulierstufe das Gemisch auf eine Maschenöffnung
von 2 mm bis 1 mm granuliert wird.
8. Verfahren nach einem der Ansprüche 5 bis 7, worin die den wirksamen Bestandteil enthaltenden
Teilchen oder die Primärgranulate oder beide mit einem langsam freisetzenden Material
(beispielsweise Methylcellulose von hoher Viskosität) trocken vermischt und anschließend
mit einer Lösung eines langsam freisetzenden Materials (zum Beispiel Methylcellulose
mit hoher Viskosität) vermischt werden.
9. Eine Formulierung mit langsamer Freisetzung nach einem der Ansprüche 1 bis 4 oder
ein Verfahren nach einem der Ansprüche 5 bis 8, worin die Formulierung für eine orale
Verabreichung formuliert wird.
Patentansprüche für folgende(n) Vertragsstaat(en): AT, ES, GR
1. Verfahren zur Herstellung einer an Menschen oder Tiere zu verabreichenden Formulierung
mit langsamer Freisetzung, umfassend ein Vermischen von einen wirksamen Bestandteil
enthaltenden Teilchen und einer Lösung oder Dispersion eines wasserlöslichen langsam
freisetzenden Materials, bei dem es sich um ein Polysaccharid oder ein Alginat handelt,
zur Ausbildung eines Agglomerats und ein Granulieren des Agglomerats, ein Trocknen
der gebildeten Primärgranulate und hierauf ein Mischen dieser Granulate mit einer
Lösung oder Dispersion eines wasserlöslichen langsam freisetzenden Materials, bei
dem es sich um ein Polysaccharid oder ein Alginat handelt, zur Ausbildung eines Agglomerats
und ein Granulieren des Agglomerats zur Ausbildung von Sekundärgranulaten mit größeren
Abmessungen als die Primärgranulate und ein Trocknen der Sekundärgranulate.
2. Verfahren nach Anspruch 1, worin der flüssige Träger jeder Lösung oder Dispersion
Wasser oder eine pharmazeutisch annehmbare organische Flüssigkeit, vorzugsweise Ethanol,
Methanol, wäßriges Ethanol, wäßriges Methanol, Chloroform, Isopropanol oder Methylenchlorid
ist.
3. Verfahren nach Anspruch 1 oder 2, worin die in der ersten und in der zweiten Mischstufe
verwendeten wasserlöslichen Materialien die gleichen sind.
4. Verfahren nach einem der vorstehenden Ansprüche, worin das langsam freisetzende Material
ein Cellulosederivat ist.
5. Verfahren nach einem der Ansprüche 1 bis 4, welches zwei Granulierstufen aufweist
und worin in der ersten Granulierstufe das Gemisch auf eine Größe von 600 µm bis 250
µm Maschenöffnung granuliert wird und in der zweiten Granulierstufe das Gemisch auf
eine Maschenöffnung von 2 mm bis 1 mm granuliert wird.
6. Verfahren nach einem der Ansprüche 1 bis 5, worin die den wirksamen Bestandteil enthaltenden
Teilchen oder die Primärgranulate oder beide mit einem langsam freisetzenden Material
(beispielsweise Methylcellulose von hoher Viskosität) trocken vermischt und anschließend
mit einer Lösung eines langsam freisetzenden Materials (zum Beispiel Methylcellulose
mit niedriger Viskosität) vermischt werden.
7. Verfahren nach einem der Ansprüche 1 bis 6, welches zusätzlich ein Vermischen der
Sekundärgranulate mit einem wasserunlöslichen langsam freisetzenden Material umfaßt.
8. Verfahren nach Anspruch 7, worin das wasserunlösliche langsam freisetzende Material
aus einem oder mehreren mineralischem, vegetabilem oder tierischem Wachs, einem C24-C62-Ester einer C12-C31-Fettsäure und eines C12-C31-Fettalkohols, einer C10-C22-Fettsäure, einem C10-C22-Fettalkohol oder einem Mono-, Di- oder Triglycerylester einer C10-C22-Fettsäure und vorzugsweise aus einem oder mehreren von hydriertem Rizinusöl, Glycerylmono-
oder - distearat, 12-Hydroxystearylalkohol oder mikrokristallinem Wachs besteht.
9. Verfahren nach einem der vorstehenden Ansprüche, worin die Formulierung für eine orale
Verabreichung formuliert wird.
Revendications pour l'(les) Etat(s) contractant(s) suivant(s): BE, CH, DE, FR, GB,
IT, LI, LU, NL
1. Formulation à libération lente à administrer à l'homme ou à l'animal, comprenant (a)
des granules primaires (1) qui comprennent des particules (3) comprenant un principe
actif et une matrice primaire (4) en matériau hydrosoluble à libération lente dans
laquelle sont dispersées les particules (3) comprenant le principe actif et (b) une
matrice secondaire (2) en matériau hydrosoluble à libération lente dans laquelle sont
dispersés les granules (1), la matrice secondaire (2) et les granules primaires (1)
formant des granules secondaires (6), un matériau polysaccharidique ou de l'alginate
formant le matériau à libération lente de l'une et/ou de l'autre des matrices (2,
4).
2. Formulation à libération lente selon la revendication 1, dans laquelle les deux matrices
(2, 4) sont faites du même matériau à libération lente.
3. Formulation à libération lente selon la revendication 1 ou la revendication 2, dans
laquelle le matériau à libération lente est un dérivé de la cellulose.
4. Formulation à libération lente selon l'une quelconque des revendications précédentes,
dans laquelle la composition matrice secondaire-granules se présente elle-même sous
la forme de granules (6) dans une phase de liant d'un matériau non hydrosoluble à
libération lente, par exemple une ou plusieurs des substances cire minérale, végétale
ou animale, ester C24-C62 d'un acide gras C12-C31 et d'un alcool gras C12-C31, acide gras C10-C22, alcool gras C10-C22, ou mono-, di- ou triglycéride formé à partir d'un acide gras C10-C22 et de préférence une ou plusieurs des substances huile de ricin hydrogénée, mono-
ou distéarate de glycéryle, alcool hydroxy-12-stéarylique ou cire microcristalline.
5. Procédé de préparation d'une formulation à libération lente à administrer à l'homme
ou à l'animal, comprenant le mélange de particules comprenant un principe actif et
une solution ou dispersion d'un matériau hydrosoluble à libération lente qui est un
polysaccharide ou un alginate pour former un agglomérat et la granulation de l'agglomérat,
le séchage des granules primaires obtenus et leur mélange à une solution ou dispersion
d'un matériau hydrosoluble à libération lente qui est un polysaccharide ou un alginate
pour former un agglomérat et la granulation de l'agglomérat pour former des granules
secondaires de taille supérieure à celle des granules primaires et le séchage des
granules secondaires et facultativement le mélange des granules secondaires à un matériau
non hydrosoluble à libération lente.
6. Procédé selon la revendication 5, dans lequel le véhicule liquide de chaque solution
ou dispersion est de l'eau ou un liquide organique pharmaceutiquement acceptable (de
préférence de l'éthanol, du méthanol, de l'éthanol aqueux, du méthanol aqueux, du
chloroforme, de l'isopropanol ou du chlorure de méthylène).
7. Procédé selon la revendication 5 ou la revendication 6, possédant deux étapes de granulation
et dans lequel le mélange est granulé à une granulométrie comprise entre 600 µm et
250 µm pendant la première étape de granulation et le mélange est granulé à une granulométrie
comprise entre 2 mm et 1 mm pendant la seconde étape de granulation.
8. Procédé selon l'une quelconque des revendications 5 à 7, dans lequel les particules
contenant du principe actif et/ou les granules primaires sont mélangés à sec à un
matériau à libération lente (par exemple de la méthylcellulose à viscosité élevée),
puis mélangés à une solution d'un matériau à libération lente (par exemple méthylcellulose
à viscosité élevée).
9. Formulation à libération lente selon l'une quelconque des revendications 1 à 4 ou
procédé selon l'une quelconque des revendications 5 à 8, dans lesquels la formulation
est formulée pour l'administration orale.
Revendications pour l'(les) Etat(s) contractant(s) suivant(s): AT, ES, GR
1. Procédé de préparation d'une formulation à libération lente à administrer à l'homme
ou à l'animal, comprenant le mélange de particules comprenant un principe actif et
d'une solution ou dispersion d'un matériau hydrosoluble à libération lente qui est
un polysaccharide ou un alginate pour former un agglomérat et la granulation de l'agglomérat,
le séchage des granules primaires obtenus et leur mélange à une solution ou dispersion
d'un matériau hydrosoluble à libération lente qui est un polysaccharide ou un alginate
pour former un agglomérat et la granulation de l'agglomérat pour former des granules
secondaires de taille supérieure à celle des granules primaires et le séchage des
granules secondaires.
2. Procédé selon la revendication 1, dans lequel le véhicule liquide de chaque solution
ou dispersion est de l'eau ou un liquide organique pharmaceutiquement acceptable,
de préférence de l'éthanol, du méthanol, de l'éthanol aqueux, du méthanol aqueux,
du chloroforme, de l'isopropanol ou du chlorure de méthylène.
3. Procédé selon la revendication 1 ou la revendication 2, dans lequel les matériaux
hydrosolubles utilisés dans la première et la deuxième étape de mélange sont identiques.
4. Procédé selon l'une quelconque des revendications précédentes, dans lequel le matériau
à libération lente est un dérivé de la cellulose.
5. Procédé selon l'une quelconque des revendications 1 à 4, possédant deux étapes de
granulation et dans lequel le mélange est granulé à une granulométrie comprise entre
600 µm et 250 µm pendant la première étape de granulation et le mélange est granulé
à une granulométrie comprise entre 2 mm et 1 mm pendant la seconde étape de granulation.
6. Procédé selon l'une quelconque des revendications 1 à 5, dans lequel les particules
contenant du principe actif et/ou les granules primaires sont mélangés à sec à un
matériau à libération lente (par exemple de la méthylcellulose à viscosité élevée),
puis mélangés à une solution/dispersion d'un matériau à libération lente (par exempte
méthylcellulose à viscosité élevée). primaires obtenus et leur mélange à une solution
ou dispersion d'un matériau hydrosoluble à libération lente qui est un polysaccharide
ou un alginate pour former un agglomérat et la granulation de l'agglomérat pour former
des granules secondaires de taille supérieure à celle des granules primaires et le
séchage des granules secondaires et facultativement le mélange des granules secondaires
à un matériau non hydrosoluble à libération lente.
6. Procédé selon la revendication 5, dans lequel le véhicule liquide de chaque solution
ou dispersion est de l'eau ou un liquide organique pharmaceutiquement acceptable (de
préférence de l'éthanol, du méthanol, de l'éthanol aqueux, du méthanol aqueux, du
chloroforme, de l'isopropanol ou du chlorure de méthylène) .
7. Procédé selon la revendication 5 ou la revendication 6, possédant deux étapes de
granulation et dans lequel le mélange est granulé à une granulométrie comprise entre
600 µm et 250 µm pendant la première étape de granulation et le mélange est granulé
à une granulométrie comprise entre 2 mm et 1 mm pendant la seconde étape de granulation.
8. Procédé selon l'une quelconque des revendications 5 à 7, dans lequel les particules
contenant du principe actif et/ou les granules primaires sont mélangés à sec à un
matériau à libération lente (par exemple de la méthylcellulose à viscosité élevée),
puis mélangés à une solution d'un matériau à libération lente (par exemple méthylcellulose
à viscosité élevée).
9. Formulation à libération lente selon l'une quelconque des revendications 1 à 4 ou
procédé selon l'une quelconque des revendications 5 à 8, dans lesquels la formulation
est formulée pour l'administration orale.